1. Field of the Invention
The present invention relates, in general, to medical devices and, in particular, to methods, systems, test strips, and calibration strips used for the determination of analytes.
2. Description of the Related Art
A variety of systems for determining an analyte (e.g., glucose) in a body fluid sample (for example, a whole blood, plasma or interstitial fluid sample) are known and documented. These systems typically include a meter, at least one test strip, either electrochemical or photometric in nature, and at least one lancet. The lancet can, if desired, be integrated with the test strip. An example of such a system is the OneTouch® Ultra from Lifescan Inc., Milpitas, USA. Further representative systems, meters and test strips are described in, for example, U.S. Pat. Nos. 6,168,957B1; 5,708,247; 6,045,567 and 6,733,655, and U.S. Patent Application Publication Nos. 2004/015102A and 2003/0207441A1, each of which is hereby incorporated in full by reference.
As the manufacturing of conventional test strips is subject to variation, a calibration code (also referred to as a test strip calibration code) is typically assigned to each lot of test strips during the manufacturing process. The calibration code, following entry into an associated meter, is used with an algorithm in the meter to compensate for test strip manufacturing variability. In this manner, an analyte can be determined accurately and precisely regardless of test strip manufacturing variation.
The calibration code assigned to the test strips within any given test strip package (e.g., vial or cassette) purchased by a user can vary from package to package. Therefore, during use of a meter and test strip, a user must ensure that the calibration code that corresponds to the test strip undergoing use has been entered into the meter. This may require that the user obtain a calibration code printed on the test strip package and manually enter that calibration code into the meter or select that calibration code from a list of calibration codes stored in the meter.
Failure to enter or select the calibration code that corresponds to a test strip undergoing use (i.e., the “correct” calibration code) can lead to inaccurate and/or imprecise determination of an analyte. Moreover, the manual entering or selecting of calibration codes is time consuming and can be inconvenient to a user.